Chapter 14 Paired Excercises

Chapter 14 Paired Excercises

4. Calculate the mass percent of the following solutions: (a) 25.0 g NaNO3 in 125.0 g H2O (c) 0.75 mol K2CrO4 in 225 g H2O

6. A reaction requires 25.0 g of sodium chloride. How many grams of a 10.0% by mass solution would provide this amount of solute?

12. Determine the volume percent of a solution made by dissolving:

(b) 4.0 mL of methanol in enough water to make 25.0 ml of solution

14. Calculate the molarity of the following solutions: (b) 2.25 mol of CaCl2 in 1.50 L of solution (c) 275 g C6H12O6 in 775 mL of solution

18. Calculate the grams of solute in each of the following solutions: (a) 1.20 L of 18 M H2SO4 (b) 27.5 mL of 1.50 M KMnO4

22. What will be the molarity of the resulting solutions made by mixing the following? Assume that volumes are additive.

(a) 175 mL of 3.0 M H2SO4 with 275 mL of H2O… (c) 50.0 mL of 0.250 M HCl with 25.0 mL of 0.500 M HCl

24. Calculate the volume of concentrated reagent required to prepare the diluted solutions indicated:

(a) 18 M H2SO4 to prepare 225 mL of 2.0 M H2SO4… (b) 15 M NH3 to prepare 75 mL of 1.0 M NH3

28. Use the equation 2 NaOH(aq) + H2SO4(aq)à Na2SO4(aq) + 2 H2O(l) , to calculate the following:

(d) the grams of Na2SO4 that can be obtained from 25 mL of 0.050 M NaOH

(e) the volume of 0.250 M H2SO4 needed to react with 25.5 mL of 0.750 M NaOH

41. How much sterile water has to be added to a vial of 100 units of Botox to create a concentration of 4 units of Botox per 0.1 mL of water?

42. A 3 year old boy weighing 16 kg was seen at the pediatrician's office and was diagnosed with an ear infection. The doctor prescribed Azithromycin, to be administered using the following dosing schedule: 10 mg/kg per day on the first day, followed by 5mg/kg, once a day, for the next four days. How many milligrams of Azithromycin does the boy need in total?

b. You reconstitute the Azithromycin to a 500mg/15ml bottle. How many mLs of Azithromycin solution are given on each of the five days of therapy?

Chapter 15 Review Questions

9. Write the Lewis structure for the (a) bromide ion, (b) hydroxide ion, and (c) cyanide ion. Why are these ions considered to be bases according to the Brønsted–Lowry and Lewis acid–base theories?

14. Calculate the [H+] for… (b) orange juice, with a pH of 3.7…. (c) a solution with a pH of 11.5

12. A solution of HCl (hydrochloric acid) in water conducts an electric current, but a solution of HCl in hexane does not. Explain this behavior in terms of ionization and chemical bonding.

20. What are the relative concentrations, (which one is there more of and which one is less?) of H+ and OH- in (a) a neutral solution, (b) an acid solution, and (c) a basic solution?

Chapter 15 Paired Excersises

2. Identify the conjugate acid–base pairs in each of the following equations:

(a) H2S + NH3 à NH4 + + HS -

(b) HSO4 - + NH3 à SO4 - + NH4+

(d) HNO3 + H2O à NO3 - + H3O+

10. Determine the molarity of each of the ions present in the following aqueous salt solutions: (assume 100% ionization)

(a) 2.25 M FeCl3

(b) 1.20 M MgSO4

14. Calculate the concentration of H+ for

(a) pure water

(b) orange juice, with a pH of 3.7

18. Given the data for the following separate titrations, calculate the molarity of the NaOH solution.

mL HCl / Molarity HCl / mL NaOH / Molarity NaOH
a / 37.19 / .0126 / 31.91 / ?
b / 48.04 / 0.482 / 24.02 / ?
c / 13.13 / 1.425 / 39.39 / ?

22. For each of the given pairs, determine which solution is more acidic. All are water solutions. Explain your answer.

(a) 1 M HCl or 2 M HCl?

(b) 1 M HNO3 or 1 M H2SO4 ?

24. Determine how many grams of Al(OH)2 will be required to neutralize 275 mL of 0.125 M HCl according to the reaction:

3 HCl(aq) + Al(OH)3(s) à AlCl3(aq) + 3 H2O(l)

32. Calculate the pH of (a) black coffee, 5 x 10-5 M H+ … (b) limewater, 3.4 x 10-11 M H+